PHP preg_replace with extension in url [duplicate]

I want to replace all href elements which contain url with file zip or pdf for example:

text = lorem inpsut http://example.com/file/file.zip lorem inspus https://example.com/file/file2.zip lorem inpus a lorem inpust http://example.com/file/file3.doc

and now i want to replace all this link to other link using preg_replace so:

http://example.com/file/file.zip - replace
https://example.com/file/file2.zip - replace
http://example.com/file/file3.doc - no replace beacuse .doc
https://example.com/file/testzip - no replace because testzip not .zip
https://example.com/file/dafsf.aszip - no replace

I figured out one:

/(\bhttps?\:\/\/|\/\/)\S+(?:.zip|.pdf)\b/gim

but it doesn't work corectly beacuse it finding also

https://example.com/file/file2.aaazip and
https://example.com/file/dafsfaszip

Could you help me?